VATS is a closed surgery technique using a few small incisions. There are no large incisions like open surgeries. When the procedure is over, perhaps one or more tubes are placed in the rib cage to drain fluid and air. The aim is to examine the chest wall and lungs with a video camera and to obtain tissue for diagnosis.
Basically, everything that can be done with open surgery can be done with VATS. However, in cases that prevent the camera or hand tools from reaching (adhesions, previous diseases or surgeries, etc.), open surgery may be necessary.
